Final answer:
William the Conqueror claimed the English throne by alleging that Harold Godwinson had pledged fealty to him. Following his victory at the Battle of Hastings in 1066, he became the first Norman King of England, significantly impacting the country's future development.
Step-by-step explanation:
William the Conqueror claimed the English throne by asserting that Harold Godwinson had pledged fealty to him, which was prominently depicted in a feudal pledge scene in the Bayeux Tapestry. This claim was one justification for William's invasion of England. In 1066, during the Battle of Hastings, William defeated King Harold II and subsequently took over as the ruling monarch, becoming the first Norman king of England. The conquest had a lasting impact on England, altering its culture, government structure, and even the language.